The present disclosure relates to transistors. Semiconductor devices are increasingly being used in consumer, industrial, and other electronic devices. The semiconductor devices may be classified as a memory device for storing data, a logic device for processing data, or a hybrid device including both of memory and logic elements. Due to the increased demand for electronic devices with fast speed and/or low power consumption, the semiconductor devices may benefit from providing high reliability, high performance, and/or multiple functions. To satisfy these technical requirements, complexity and/or integration density of semiconductor devices may increase.